Vampire Diaries' Taylor Kinney on the Moonstone: "It's More Powerful Than You'd Think"

When Mason Lockwood strolled into Mystic Falls at the start of Season 2, the Salvatore Brothers were on alert. As if learning he's a werewolf wasn't threatening enough, the last episode of The Vampire Diaries' revealed he's in cahoots with Katherine — everyone's vampire enemy. Taylor Kinney, who plays Mason on the CW series (Thurs, 8/7c), insists that he returned in large part to mentor his nephew Tyler (Michael Trevino). The actor talks about whether he believes his character has fallen under Katherine's spell, and what that moonstone really does.

TVGuide.com: What do you know about the history between Mason and Katherine?Taylor Kinney: I know that they've known each other for a year or so, and it's a love affair. Maybe more on his part.

TVGuide.com: Do you think she's just using him like she does with everyone else?Kinney: He's not [that] naïve. It's not like you fall for a girl and then you've got your blinders on and put yourself out there to get worked. Mason's not like that. I can't say he's going to be just another notch on the bedpost for Katherine in terms of people she's worked to her own advantage. I just don't see him being a pawn.

TVGuide.com: Did Mason really return to Mystic Falls for Tyler?Kinney: Of course, that's his blood. He does want to mentor Tyler, and he does have good in him. He bounced out of town for awhile ... so there's always going to be variables in that and question marks in intentions and motivations.

TVGuide.com: What can you say about the moonstone?Kinney: I know it has a sh-- load of power [and] I can say that it's more powerful than you'd think. Once it is revealed, if it is revealed, it doesn't make you grow an extra tail.

TVGuide.com: Can it trump the vampires' ring?Kinney: I certainly hope so. I'm going through a lot of trouble to get that damn thing, it better be worth it. It better not just allow me to walk in certain weather.

TVGuide.com: Will the tension between Mason and Damon progress?Kinney: It's been a boxing match from the start. Mason was trying to be cool; he didn't come to Mystic Falls to kill vampires. It's why he chains himself up ... because he knows what can happen if he does turn. Mason offers a hand and says, "Let's squash this and be cool, I'm not your enemy," and then [Damon] tries to kill Mason. There's a huge amount of tension there and every week it's going to escalate. They're not going to be sitting at the bar drinking beers anytime soon.

TVGuide.com: How is being on The Vampire Diaries different from your previous series, Trauma?Kinney: It's so different. Spending a year in San Francisco working on a medical drama was great and I got to be pretty close with paramedics, firemen and police in the area. The fans of the show were in large part the medical community. With Vampire Diaries, the fans are just rabid and run the spectrum. You have fans who are kids and fans in their 30s and 40's. I have friends of mine who are burly dudes with big beards, ride Harleys, and they watch it. They're like, "You're going to be on that show? I love that show." I'm like, "You're kidding me right?" He's like, "No, it brings out the 16-year-old girl in me."